Article IV, Section. 4.
The United States shall guarantee to every State in this Union a
Republican
Form of Government...Amendment XIV, Section 1.
...[N]or shall any State...deny to any person within its jurisdiction
the
equal protection of the laws.

MR. JUSTICE BRENNAN delivered the opinion of the Court.

This civil action was brought under 42 U.S.C. 1983 and 1988 to
redress
the alleged deprivation of federal constitutional rights. The
complaint,
alleging that by means of a 1901 statute of Tennessee apportioning the
members of the General Assembly among the State's 95 counties, these
plaintiffs
and others similarly situated, are denied the equal protection of the
laws
accorded them by the Fourteenth Amendment to the Constitution of the
United
States by virtue of the debasement of their votes," was dismissed by a
three-judge court. The court held that it lacked jurisdiction of the
subject
matter and also that no claim was stated upon which relief could be
granted.
We noted probable jurisdiction of the appeal. We hold that the
dismissal
was error, and remand the cause to the District Court for trial and
further
proceedings consistent with this opinion....

Tennessee's standard for allocating legislative representation among
her counties is the total number of qualified voters resident in the
respective
counties, subject only to minor qualifications. Decennial
reapportionment
in
compliance with the constitutional scheme was effected by the General
Assembly
each decade from 1871 to 1901.... In 1901 the General Assembly
abandoned
separate enumeration in favor of reliance upon the Federal Census and
passed
the Apportionment Act here in controversy. In the more than 60 years
since
that action, all proposals in both Houses of the General Assembly for
reapportionment
have failed to pass.

Between 1901 and 1961, Tennessee has experienced substantial growth
and redistribution of her population. In 1901 the population was
2,020,616,
of whom 487,380 were eligible to vote. The 1960 Federal Census reports
the State's population at 3,567,089, of whom 2,092,891 are eligible to
vote. The relative standings of the counties in terms of qualified
voters
have changed significantly. It is primarily the continued application
of
the 1901 Apportionment Act to this shifted and enlarged voting
population
which gives rise to the present controversy.

Indeed, the complaint alleges that the 1901 statute, even as of the
time of its passage, "made no apportionment of Representatives and
Senators
in accordance with the constitutional formula . . ., but instead
arbitrarily
and capriciously apportioned representatives in the Senate and House
without
reference . . . to any logical or reasonable formula whatever." It is
further
alleged that "because of the population changes since 1900, and the
failure
of the Legislature to reapportion itself since 1901," the 1901 statute
became "unconstitutional and obsolete." Appellants also argue that,
because
of the composition of the legislature effected by the 1901
Apportionment
Act, redress in the form of a state constitutional amendment to change
the entire mechanism for reapportioning, or any other change short of
that,
is difficult or impossible. The complaint concludes that "these
plaintiffs
and others similarly situated, are denied the equal protection of the
laws
accorded them by the Fourteenth Amendment to the Constitution of the
United
States by virtue of the debasement of their votes." They seek a
declaration
that the 1901 statute is unconstitutional and an injunction restraining
the appellees from acting to conduct any further elections under it.
They
also pray that unless and until the General Assembly enacts a valid
reapportionment,
the District Court should either decree a reapportionment by
mathematical
application of the Tennessee constitutional formulae to the most recent
Federal Census figures, or direct the appellees to conduct legislative
elections, primary and general, at large. They also pray for such other
and further relief as may be appropriate.

I.

The dismissal order recited that the court sustained the appellees'
grounds
"(1) that the Court lacks jurisdiction of the subject matter, and (2)
that
the complaint fails to state a claim upon which relief can be granted .
. . ."

In the setting of a case such as this, the recited grounds embrace
two
possible reasons for dismissal:

First: That the facts and injury alleged, the legal bases invoked as
creating the rights and duties relied upon, and the relief sought, fail
to come within that language of Article III of the Constitution and of
the jurisdictional statutes which define those matters concerning which
United States District Courts are empowered to act;

Second: That, although the matter is cognizable and facts are
alleged
which establish infringement of appellants' rights as a result of state
legislative action departing from a federal constitutional standard,
the
court will not proceed because the matter is considered unsuited to
judicial
inquiry or adjustment.

We treat the first ground of dismissal as "lack of jurisdiction of
the
subject matter." The second we consider to result in a failure to state
a justiciable cause of action....

II.

JURISDICTION OF THE SUBJECT MATTER.

The District Court was uncertain whether our cases withholding federal
judicial relief rested upon a lack of federal jurisdiction or upon the
inappropriateness of the subject matter for judicial consideration -
what
we have designated "nonjusticiability." The distinction between the two
grounds is significant. In the instance of nonjusticiability,
consideration
of the cause is not wholly and immediately foreclosed; rather, the
Court's
inquiry necessarily proceeds to the point of deciding whether the duty
asserted can be judicially identified and its breach judicially
determined,
and whether protection for the right asserted can be judicially molded.
In the instance of lack of jurisdiction the cause either does not
"arise
under" the Federal Constitution, laws or treaties (or fall within one
of
the other enumerated categories of Art. III, 2), or is not a "case or
controversy"
within the meaning of that section; or the cause is not one described
by
any jurisdictional statute. Our conclusion that this cause presents no
nonjusticiable "political question" settles the only possible doubt
that
it is a case or controversy. Under the present heading of "Jurisdiction
of
the Subject Matter" we hold only that the matter set forth in the
complaint
does arise under the Constitution and is within 28 U.S.C. 1343.

Article III, 2, of the Federal Constitution provides that "The
judicial
Power shall extend to all Cases, in Law and Equity, arising under this
Constitution, the Laws of the United States, and Treaties made, or
which
shall be made, under their Authority . . . ." It is clear that the
cause
of action is one which "arises under" the Federal Constitution....

Since the complaint plainly sets forth a case arising under the
Constitution,
the subject matter is within the federal judicial power defined in Art.
III, 2, and so within the power of Congress to assign to the
jurisdiction
of the District Courts. Congress has exercised that power...An unbroken
line of our precedents sustains the federal courts' jurisdiction of the
subject matter of federal constitutional claims of this nature....

IV.

JUSTICIABILITY.

In holding that the subject matter of this suit was not justiciable,
the
District Court relied on Colegrove v. Green and subsequent per curiam
cases.
The court stated: "From a review of these decisions there can be no
doubt
that the federal rule . . . is that the federal courts . . . will not
intervene
in cases of this type to compel legislative reapportionment." We
understand
the District Court to have read the cited cases as compelling the
conclusion
that since the appellants sought to have a legislative apportionment
held
unconstitutional, their suit presented a "political question" and was
therefore
nonjusticiable. We hold that this challenge to an apportionment
presents
no nonjusticiable "political question." The cited cases do not hold the
contrary.

Of course the mere fact that the suit seeks protection of a
political
right does not mean it presents a political question. Such an objection
"is little more than a play upon words." Rather, it is argued
that
apportionment cases, whatever the actual wording of the complaint, can
involve no federal constitutional right except one resting on the
guaranty
of a republican form of government, and that complaints based on that
clause
have been held to present political questions which are nonjusticiable.

We hold that the claim pleaded here neither rests upon nor
implicates
the Guaranty Clause and that its justiciability is therefore not
foreclosed
by our decisions of cases involving that clause. The District Court
misinterpreted
Colegrove v. Green and other decisions of this Court on which it
relied.
Appellants' claim that they are being denied equal protection is
justiciable,
and if discrimination is sufficiently shown, the right to relief under
the equal protection clause is not diminished by the fact that the
discrimination
relates to political rights."

Our discussion, even at the price of extending this opinion,
requires
review of a number of political question cases, in order to expose the
attributes of the doctrine - attributes which, in various settings,
diverge,
combine, appear, and disappear in seeming disorderliness. Since that
review
is undertaken solely to demonstrate that neither singly nor
collectively
do these cases support a conclusion that this apportionment case is
nonjusticiable,
we of course do not explore their implications in other contexts. That
review reveals that in the Guaranty Clause cases and in the other
"political
question" cases, it is the relationship between the judiciary and the
coordinate
branches of the Federal Government, and not the federal judiciary's
relationship
to the States, which gives rise to the "political question."

We have said that "In determining whether a question falls within
[the
political question] category, the approriateness under our system of
government
of attributing finality to the action of the political departments and
also the lack of satisfactory criteria for a judicial determination are
dominant considerations." The nonjusticiability of a political
question
is primarily a function of the separation of powers. Much confusion
results
from the capacity of the "political question" label to obscure the need
for case-by-case
inquiry. Deciding whether a matter has in any measure been committed by
the Constitution to another branch of government, or whether the action
of that branch exceeds whatever authority has been committed, is itself
a delicate exercise in constitutional interpretation, and is a
responsibility
of this Court as ultimate interpreter of the Constitution. To
demonstrate
this requires no less than to analyze representative cases and to infer
from them the analytical threads that make up the political question
doctrine.
We shall then show that none of those threads catches this case.

Foreign relations: There are sweeping statements to the effect that
all questions touching foreign relations are political questions. Not
only
does resolution of such issues frequently turn on standards that defy
judicial
application, or involve the exercise of a discretion demonstrably
committed
to the executive or legislature; but many such questions uniquely
demand
single-voiced statement of the Government's views. Yet it is error to
suppose
that every case or controversy which touches foreign relations lies
beyond
judicial cognizance. Our cases in this field seem invariably to show a
discriminating analysis of the particular question posed, in terms of
the
history of its management by the political branches, of its
susceptibility
to judicial handling in the light of its nature and posture in the
specific
case, and of the possible consequences of judicial action....

Validity of enactments: In Coleman v. Miller, supra, this Court held
that the questions of how long a proposed amendment to the Federal
Constitution
remained open to ratification, and what effect a prior rejection had on
a subsequent ratification, were committed to congressional resolution
and
involved criteria of decision that necessarily escaped the judicial
grasp.
Similar considerations apply to the enacting process: "The respect due
to coequal and independent departments," and the need for finality and
certainty about the status of a statute contribute to judicial
reluctance
to inquire whether, as passed, it complied with all requisite
formalities.
But it is not true that courts will never delve into a legislature's
records
upon such a quest: If the enrolled statute lacks an effective date, a
court
will not hesitate to seek it in the legislative journals in order to
preserve
the enactment. The political question doctrine, a tool for maintenance
of governmental order, will not be so applied as to promote only
disorder....

It is apparent that several formulations which vary slightly
according
to the settings in which the questions arise may describe a political
question,
although each has one or more elements which identify it as essentially
a function of the separation of powers. Prominent on the surface of any
case held to involve a political question is found a textually
demonstrable
constitutional commitment of the issue to a coordinate political
department;
or a lack of judicially discoverable and manageable standards for
resolving
it; or the impossibility of deciding without an initial policy
determination
of a kind clearly for nonjudicial discretion; or the impossibility of a
court's undertaking independent resolution without expressing lack of
the
respect due coordinate branches of government; or an unusual need for
unquestioning
adherence to a political decision already made; or the potentiality of
embarrassment from multifarious pronouncements by various departments
on
one question.

Unless one of these formulations is inextricable from the case at
bar,
there should be no dismissal for nonjusticiability on the ground of a
political
question's presence....

But it is argued that this case shares the characteristics of
decisions
that constitute a category not yet considered, cases concerning the
Constitution's
guaranty, in Art. IV, 4, of a republican form of government. A
conclusion
as to whether the case at bar does present a political question cannot
be confidently reached until we have considered those cases with
special
care. We shall discover that Guaranty Clause claims involve those
elements
which define a "political question," and for that reason and no other,
they are nonjusticiable. In particular, we shall discover that the
nonjusticiability
of such claims has nothing to do with their touching upon matters of
state
governmental organization....

But the only significance that Luther could have for our immediate
purposes
is in its holding that the Guaranty Clause is not a repository of
judicially
manageable standards which a court could utilize independently in order
to identify a State's lawful government. The Court has since refused to
resort to the Guaranty Clause - which alone had been invoked for the
purpose
- as the source of a constitutional standard for invalidating state
action....

We come, finally, to the ultimate inquiry whether our precedents as
to what constitutes a nonjusticiable "political question" bring the
case
before us under the umbrella of that doctrine. A natural beginning is
to
note whether any of the common characteristics which we have been able
to identify and label descriptively are present. We find none: The
question
here is the consistency of state action with the Federal Constitution.
We have no question decided, or to be decided, by a political branch of
government coequal with this Court. Nor do we risk embarrassment of our
government abroad, or grave disturbance at home if we take issue with
Tennessee
as to the constitutionality of her action here challenged. Nor need the
appellants, in order to succeed in this action, ask the Court to enter
upon policy determinations for which judicially manageable standards
are
lacking. Judicial standards under the Equal Protection Clause are well
developed and familiar, and it has been open to courts since the
enactment
of the Fourteenth Amendment to determine, if on the particular facts
they
must, that a discrimination reflects no policy, but simply arbitrary
and
capricious action.

This case does, in one sense, involve the allocation of political
power
within a State, and the appellants might conceivably have added a claim
under the Guaranty Clause. Of course, as we have seen, any reliance on
that clause would be futile. But because any reliance on the Guaranty
Clause
could not have succeeded it does not follow that appellants may not be
heard on the equal protection claim which in fact they tender. True, it
must be clear that the Fourteenth Amendment claim is not so enmeshed
with
those political question elements which render Guaranty Clause claims
nonjusticiable
as actually to present a political question itself. But we have found
that
not to be the case here....

We conclude then that the nonjusticiability of claims resting on the
Guaranty Clause which arises from their embodiment of questions that
were
thought "political," can have no bearing upon the justiciability of the
equal protection claim presented in this case....

We conclude that the complaint's allegations of a denial of equal
protection
present a justiciable constitutional cause of action upon which
appellants
are entitled to a trial and a decision. The right asserted is within
the
reach of judicial protection under the Fourteenth Amendment.

MR. JUSTICE FRANKFURTER, whom MR. JUSTICE HARLAN joins,
dissenting.

The Court today reverses a uniform course of decision established by
a dozen cases, including one by which the very claim now sustained was
unanimously rejected only five years ago. The impressive body of
rulings
thus cast aside reflected the equally uniform course of our political
history
regarding the relationship between population and legislative
representation
- a wholly different matter from denial of the franchise to individuals
because of race, color, religion or sex. Such a massive repudiation of
the experience of our whole past in asserting destructively novel
judicial
power demands a detailed analysis of the role of this Court in our
constitutional
scheme. Disregard of inherent limits in the effective exercise of the
Court's
"judicial Power" not only presages the futility of judicial
intervention
in the essentially political conflict of forces by which the relation
between
population and representation has time out of mind been and now is
determined.
It may well impair the Court's position as the ultimate organ of "the
supreme
Law of the Land" in that vast range of legal problems, often strongly
entangled
in popular feeling, on which this Court must pronounce. The Court's
authority
- possessed of neither the purse nor the sword - ultimately rests on
sustained
public confidence in its moral sanction. Such feeling must be nourished
by the Court's complete detachment, in fact and in appearance, from
political
entanglements and by abstention from injecting itself into the clash of
political forces in political settlements.

A hypothetical claim resting on abstract assumptions is now for the
first time made the basis for affording illusory relief for a
particular
evil even though it foreshadows deeper and more pervasive difficulties
in consequence. The claim is hypothetical and the assumptions are
abstract
because the Court does not vouchsafe the lower courts - state and
federal
- guidelines for formulating specific, definite, wholly unprecedented
remedies
for the inevitable litigations that today's umbrageous disposition is
bound
to stimulate in connection with politically motivated reapportionments
in so many States. In such a setting, to promulgate jurisdiction in the
abstract is meaningless. It is as devoid of reality as "a brooding
omnipresence
in the sky," for it conveys no intimation what relief, if any, a
District
Court is capable of affording that would not invite legislatures to
play
ducks and drakes with the judiciary. For this Court to direct the
District
Court to enforce a claim to which the Court has over the years
consistently
found itself required to deny legal enforcement and at the same time to
find it necessary to withhold any guidance to the lower court how to
enforce
this turnabout, new legal claim, manifests an odd - indeed an esoteric
- conception of judicial propriety. One of the Court's supporting
opinions,
as elucidated by commentary, unwittingly affords a disheartening
preview
of the mathematical quagmire (apart from divers judicially
inappropriate
and elusive determinants) into which this Court today catapults the
lower
courts of the country without so much as adumbrating the basis for a
legal
calculus as a means of extrication. Even assuming the indispensable
intellectual
disinterestedness on the part of judges in such matters, they do not
have
accepted legal standards or criteria or even reliable analogies to draw
upon for making judicial judgments. To charge courts with the task of
accommodating
the incommensurable factors of policy that underlie these mathematical
puzzles is to attribute, however flatteringly, omnicompetence to
judges.
The Framers of the Constitution persistently rejected a proposal that
embodied
this assumption and Thomas Jefferson never entertained it.....